1. Field of the Invention
The present invention relates to a bulk envelope transfer container, and, more particularly, to such a container which includes a plurality of elongate envelope receiving chambers. Each chamber includes an electromechanically controllable gate mechanism at one end thereof. The gate mechanisms are controllable such that the gate of a selected chamber can be lowered and envelopes loaded from an envelope manufacturing machine or the like, with the gate then being raised to a closed position to hold the loaded envelopes in the chamber. During such loading, the container is placed on a positioning table which is selectively operable to move the container vertically and horizontally to align specific ones of said chambers with a loading surface of the envelope manufacturing machine. For unloading, the positioning table can be used to selectively position each chamber in alignment with an envelope hopper for an automatic letter stuffer or the like.
2. Description of the Related Art
Envelope manufacturing in general has increasingly become a highly automated operation. In the production of standard and specialty envelopes, large, complex machines serve to fold blanks, apply patches, and place adhesive on the side and top or seal flaps. The side flaps are folded over and sealed and the finished envelopes are normally output via a delivery spider into a horizontal stack onto a delivery surface to be accumulated into stacks of envelopes, generally containing from 500 to 2000 envelopes. The stacks are accumulated and transferred for other operations, such as loading into cartons.
In the past, once they were machine delivered onto the loading surface, these horizontal stacks of envelopes were further manipulated one by one, often by hand, for further processing and/or for loading into boxes for shipment to a customer. In the case of specialty envelopes for bulk mailing customers, the boxes of envelopes would then be unloaded by hand at the customer's place of business and placed into automatic equipment such as letter stuffers and the like.
Modern stuffing machines are capable of operation speeds reaching or exceeding 15,000 envelopes per hour. At these speeds, it takes a full time employee to keep an stuffing machine feed hopper full by manually removing envelopes from shipping cartons and placing them in stacks on the feed hopper.
Thus, there are often many thousands of specialty envelopes in a single shipment to a customer, with each stack of envelopes in the shipment requiring manual loading into a carton, the cartons being loaded into crates and shipped. At the customer end, the crates are then manually unpacked, the individual cartons removed, opened, and the envelopes loaded into stuffer feed hoppers by hand.
There are a number of problems inherent in this repetitive use of manual labor for processing bulk specialty envelopes. First, the use of manual labor is expensive, when compared to automated equipment. In the case of automatic stuffers, if envelopes were not required to be loaded by hand, a single worker could service several machines, instead of having one worker per machine, as is the current custom. Second, the workers themselves face a problem in handling the envelope stacks, i.e., once they are picked up by compressing the stacks inwardly from the ends, the envelopes tend to spring outward, often causing envelopes to loosen and drop out, thus causing the stacks to fall apart. This means that the workers must manually exert a considerable compensating force inward against the bottom edges of the envelope stack, effectively squeezing the stack bottom to prevent the stacks from falling apart as they are lifted. Even with these precautions, it is all too common for envelope stacks to be dropped, with resulting waste and inefficiency at both the manufacturing and the end processing facilities.
Finally, the handling of the stacks leads to the third problem, which is that these repetitious manual lifting, squeezing and turning motions, when repeated hour after hour and day after day, frequently cause the affected workers to develop carpal tunnel syndrome. This is an extremely painful nerve, muscle and ligament irritation in the wrists and hands which can cause temporary and even permanent disability in the workers. In addition to the problem of the resulting pain and suffering, these injuries represent a considerable financial strain in the form of workmen's compensation, lost wages, sick leave, etc. to an envelope manufacturer, and, conceivably, even to a large volume bulk mailing facility.
It is clear then, that a need exists for an automated system and method for loading and transferring bulk envelopes from a manufacturing facility to a bulk mailer or other end user, which may be an operation in the same facility. Such a system should be capable of reliably loading multiple horizontal stacks of envelopes into a bulk container, securing the envelopes in the container, transferring the bulk container to the end user, whether in the same plant as the manufacturer or in a distant facility, and allowing the end user to use automated equipment to offload the envelopes from the container.